Tropical rainforests once covered 14% of the Earth's land but now only cover 6%, and experts say the last remaining forests could be destroyed within 40 years. Tropical rainforests are characterized by year-round high temperatures and rainfall. They have several distinct layers including an emergent layer with the tallest trees reaching 50-80 meters, a canopy layer from 20-30 meters, and an undergrowth layer with sparse vegetation. Rainforests provide many benefits such as being habitats for biodiversity, sources of medicines and timber, and helping regulate the Earth's climate by absorbing carbon dioxide. However, they are being destroyed for agriculture, logging and other human activities.

1. UNIT 3:TROPICAL RAINFOREST
• Did you know?
We are losing Earth's
greatest biological treasures
just as we are beginning to
appreciate their true value.
Rainforests once covered
14% of the earth's land
surface; now they cover a
mere 6% and experts
estimate that the last
remaining rainforests could
be consumed in less than 40
years.

2. WHAT ARE WE INVESTIGATING?
TROPICAL RAINFOREST
• What are Tropical Rainforest?
• Where are they located?

3. YOU WILL LEARN TO
• use photographs and sketches to describe
the characteristics of Tropical rainforest
• describe how Tropical rainforest adapt to
the tropical climate
• describe the uses and importance of
Tropical rainforest respect different people’s
perspectives about rainforest

4. CHARACTERISTICS OF TROPICAL
RAINFOREST
General Characterises
Description -- thick and luxuriant evergreen
forest
Suitable Climate-- high rainfall and high
temperature throughout the year
Evergreen trees – do
not shed all their
leaves at the same
time

5. CHARACTERISTICS OF TROPICAL
RAINFOREST
How can we study the rainforest?
Diversity of
plant
species
Structure of
the forest
Adaptation
of plants

6. STRUCTURE OF RAINFOREST
80
Formed
by the
crown of
the trees
Emergent
50
30
Lianas and
epiphytes
grow in this
layer
Canopy
20
Undergrowth Layer
Forest floor
0
Plants
here are
widely
spaced
Sparse
vegetation
with leaf
litter

7. * tallest
trees are the
emergent
* towering above the
canopy
* rising as much as 5080metres above the
forest floor.
* Eg Tualang and Kapok
trees.
Emergent layer
* Trees
grow to heights
20-30 metres to reach
sunlight.
* Form a continuous
cover locking 90% of
sunlight
* Eg includes ferns
Canopy Layer
* It's very dark down here.
Little sunshine reaches this
area
*larger leaves to reach the
sunlight.
*plants seldom grow to 20
metres.
* hardly any sun reaches
the forest floor things begin
to decay quickly.
Undergrowth Layer

8. HOMEWORK
• Read Pages 75 to 76 from textbook
• Do exercise 3.1 and 3.2 (pages 37-40)
from your workbook.
• (you may refer to slide 6 of your notes and pg. 79 of your
textbook to help you draw the sketch of the rainforest)

9. DISCOVER THE DIFFERENT SPECIES
FOUND IN THE TROPICAL RAINFOREST
The world's
largest honey
bees home:
_____________
Forms lush
carpet of
greenery:
_______
Makes good
household
plants :
_________
Used as
medicinal or
craft purposes:
____________
The giant of
the Amazon
Rainforest :
____________
Found on
Singapore
rain trees:
____________
Grows well with
nutrients from
decomposed :
____________

10. DISCOVER THE DIFFERENT SPECIES
FOUND IN THE TROPICAL RAINFOREST
The world's
largest
honey bees
home:
Tualang tree
Forms lush
carpet of
greenery:
mosses
Makes good
household
plants :
Staghorn
ferns
Used as
medicinal or craft
purposes:
Monkey Ladder
vines
The giant of
the Amazon
Rainforest :
Kapok tree
Found on
Singapore rain
trees:
Bird’s Nest Fern
Grows well with
nutrients from
decomposed
Fungi

11. Water
catchment
Green
lungs of
the
earth
Habitat to
flora and
fauna
Uses of
Tropical
Rainforest
Habitat to
indigenous
people
Source
of
timber
Medical
application

12. • An area drained by a river and the smaller rivers
that flow into it.
• Rain water that drips from trees seeps into the
ground and is stored as ground water so Tropical
Rainforest are large water catchment areas.
• Impurities are trapped by the soil before it flows
onto the reservoirs .
• The Central catchment reserve lies within the
biggest water catchment in Singapore

13. CENTRAL CATCHMENT NATURE
RESERVE

14. GREEN LUNG OF THE EARTH
• Forest absorb carbon dioxide from the atmosphere
and release oxygen through photosynthesis.
• Forest helps the earth to “breath” so its called
“green lungs of the earth.”
• 20% of earth oxygen is generated by the Amazon
rainforest.
• Forest acts as the earth’s natural purifier and the
dense vegetation keeps it cool.

15. • Rainforest is home to 2 million of the world’s
plants, animals, insects and a variety of fungi.
• Ample sunlight allows plants to thrive which in
becomes food to animals.
• The canopy allows other plants and animals to
survive.
• Indigenous people obtain food through hunting or
as shifting cultivators and depend on the rainforest
for basic necessities too.

16. • Forest provide wood for fuel for cooking.
• Tropical rainforest supply one-fifth of the world's
industrial timber .
• Teak, ebony, mahogany and meranti are valued
for their strength, durability, texture and beauty.
• Products made include
doors, window frames and furniture

17. • Tropical Rainforest is the world’s largest pharmacy
source of medicine
• Brazil nuts have cancer-fighting prosperities
• Cinchona tree – treats Malaria
• Madagascar periwinkle plant– treats childhood
leukaemia
• Clavillia plants treats eczema & itchiness

18. WHICH PHOTOGRAPH SHOWS A TROPICAL
RAINFOREST ?
Figure B
Figure A
What factors did you consider to make your decision?

19. GEOGRAPHICAL INVESTIGATION
SKILLS
A SCHOOL-BASED ACTIVITY- SKETCHING
• Observe how the trees in the school field adapt to
our climate.
• Take a photo of the tree that shows a characteristics
of the adaptation.
• Using the skills studied in Unit 2 and with reference
to Pg. 79 of the textbook, sketch the feature you
see.
• Paste your sketch and the photo on a A4 paper and
submit to your teacher